Gyroscope construction



Aug. 10, 1948. F P STROTHER 2,446,727

GYROSGOPE CONSTRUCTION Filed sept. 21, 1945 IN VEN TOR. /r/ffl) l".5770777167? Patented ug. l0, 1948 GYROSCOPE CONSTRUCTION Fred P.Strother, Minneapolis, Minn., assigner to Minneapolis-HoneywellRegulator Company,

Minneapolis, Minn., a corporation of Delaware Application September 21,1945, Serial No. 617,775

This invention relates to an improved gyroscope construction and moreparticularly to erector or corrector means to be used in conjunctionwith gyroscopes.

In gyroscope constructions, it is customary to provide some means tomaintain the spin axis thereof in a position relative to the earthssurface. Such means are commonly referred to as erectors or correctors.An extensively used type of erector comprises an unbalanced memberdriven about an axis normally perpendicular to the earths surface.

Although the rotation of the unbalanced member about its axis creates aforce which causes a slight circular precession of the gyroscope, thespin axis thereof is maintained in a substantially predeterminedposition if the speed of the unbalanced member is constant throughouteach rotation. However, a tilting of the gyroscope moves the axis of theunbalanced member from its vertical plane and the circular path of theunbalanced member then becomes inclined upwardly on one side anddownwardly on the other in the direction of its travel. The drive meansfor the unbalanced member is adapted to rotate it at a uniform andconstant rate so long as it moves on a horizontal plane. But when theaxis is tilted so that the circular path is uphill on one side anddownhill on the other side, the rate of the unbalanced member variesover the different portions of its course. Accordingly, slip friction orother drive means for the unbalanced member must be precisely andaccurately adjusted to permit slow movement over the uphill portion andfast movement over the downhill portion of the circular path. rI'hisuneven rate of travel must be accurately controlled to cause gyroscopicprecession to restore the spin axis of the gyroscope and the axis of theunbalanced member to their predetermined positions without overheating.

Various means have been devised for driving such unbalanced erectormembers. These range from slip friction arrangements operably connectedto the gyroscope driving mechanism to separate power means such as airjets or the like. In each of these drive means careful and frequentservice and adjustments are required. The engaging surfaces of the slipfriction arrangements tend to glaze, wear or become otherwise impairedwhereby operation of the device becomes erratic and unpredictable. inaddition to requiring separate means for maintaining a constantoperating pressure also requires frequent and highly specialized serviceand adjustment. Moreover, gyroscope constructions having such drivingmeans for their mechanical erectors also require considerable closetolerance work in their manufacture. In addition to such devices beingcostly, extremely fragile, and requiring frequent skilled service, someof the ref- The air jet source of power 15 Claims. (Cl. 'Z4-5) quiredadjustments and replacements can only be made at the factory or'at baseswhere special equipment and highly trained personnel are available.Consequently, such structures are often out of service for long periodsof time.

In the present construction, the objectionable features above set forthhave been totally obviated or materially reduced. The improved device ofthis invention is capable of functioning accurately and dependably overprolonged periods of time without any servicing or attention whatsoever.

One of the principal objects of importance and advantage of the improveddevice of this invention resides in the provision of means for utilizinga liquid drive connection between a gyroscope drive means and anunbalanced erector member. l.

Another object of importance 4and advantage is the provision of meansfor applying a yieldable resistance to retard movement -of the erectormember. The yieldable resistance may be varied to control the rate ofmovement of the erector member.

A further object of the present invention is the provision of means foreconomically producing a highly e'cient and dependable structure ofalimited number of associated parts which readily lend themselves tomass production manufacture.

Still another object of importance is the provision of means forproducing a sturdy and rugged device in which upkeep, adjustment, andinspection requirements to insure long and proper functioning of theimproved device are reduced to a minimum.

A further object of importance and advantage of the present constructionis the provision of means whereby such infrequent inspection, servicingand even replacement of parts as may be required may be made without theaid of special tools or equipment and Without removingY the device fromits installed position.

Additional objects of advantage and importance will become apparent asthe following detailed description progresses, reference being had t theaccompanying drawing wherein Figure 1 is an elevational view of agyroscope construction which embodies the invention;Y Y

Figure 2 is a top .plan View thereof; Y`

Figure 3 is a slightly enlarged top plan view of the erector portion ofthe device, the vcover thereof being removed; and f Figure 4 is asectional View taken on lines lL-fi of Figure 3. y

The reference numeral lil indicates generally a gyroscope which in theembodiment shown is universally mounted in the Cardan ring assembly l2.The Cardan ring assembly l2 may besup'- ported by a frame I4 or by othersuitable means. In the embodiment here shown for the purpose ofillustration, the gyroscope I includes a housing member l vin `which arotorpnot shown, is operably pbsitioned.l .The structure v'includes `.a

rotor shaft I6, to which the rotor is fixed, journaled in the housingmember. A portion of the.

rotor shaft I6 extends upwardly through .the top of the housing memberl5 as is best shownin` Figure 4.

Positioned on the housing 1 lyandlpreferably secured thereto as byWelding or. the .'like,z.is a centrally apertured circular vessel I1.The aperture in the vessel Il is aligned 'with an aperture in thehousing member l5 through whichpthe rotor shaft I6 extends., Thus therotor shaft I6 may extend into lthe vessel I1 as hereinafter more fullydescribed.- The vesselll is provided with a cover i8 whichmay'be.detachably secured thereto as by screws `I5! to .hermetically seal theinterior thereof from .atmosphere- Rotatably positionedwithin the vessel.l1 is an unbalanced member 20. The unbalanced member 20. is,,preferably circular. in plan' and the peripheralsur-face thereof maybe-serrated or kerfed 23,1.'as. isnbest shown in Figure-3. The depth andspacing Aof the kerfs 23 may be varied to meet specific requirements aswill hereinafter be more fully explained. The rotor shaft yI6 -extendsupwardly through an aperture in .the-Tunbalanced `member 20, as isbestshown in Figure 4, to provide an. axis about which the member may bevrotated.

In the preferred construction of the unbalanced member a circular.recess 24 is formed eccentricallyvof rthe member. Thus, the member 2l,:asshownin Figure 3, has alight left side and a heavy :righ-t side. Itwill be apparent, however, that the .circular recessmay be lotherwiselocated and the unbalance of the member may .beprovdedinother suitableways. Projecting radially .from theperipheralzsurface Aof therecess 2li4for a `purpose hereinafter more fully-to appear ,is an ahutmentmember25. While only one Yabutment Vmember 25. .is shown .in the illustration,it will be apparent that additional. abutment members may .beemployedWhere it: is. so desired.

vFixed to the Vportion-of the shaft I6 extending intothe .recess 24 isan impeller 26. The impeller V26 is. here shownin the .form of ,a paddlewhich, upon rotation of the shaft I6, functions to .drive a liquidcontainedin the recess 24- against the abut- :mentimember 25 andlthereby.rotate the unbalanced member 20 aboutits axis., Itis to benotedthataquantity Vof liquid,A indicated by the dotted lines inFigure 4, is.positioned inthe vessel. I1 as wellas, inthe recess 24. Asuitablesealing member 2|, which is bestv shown in Figure 4.preventsleakage of the liquid ,through the aperture and along the shaft I 6. Itis also to be noted that the liquidwithin the recess 24 functions underthe operation of the 4impeller -26 to rotate the unbalancedfvmember 20and that the liquid within the vesselll by contact with the peripheralface of the unbalanced member 20 functions to retard .rotative movementthereof. The retarding drag .of the liquid on the rotating vmember 42|)may be controlled by the depth of .the lkerfs or the viscosity of theVliquid in the Vvessel l'l.r It will` also be apparent that the rate ofrotation of .the -unbalanced member 2U in its operative movement .may beat an entirely different rate than the .rotational rate of the impellermember 26. Moreoverthis.rate may be varied without changing theratexofthe impeller member 26 by increasing or..decreasing the effectivedriving force exerted l on the unbalanced member 20 or increasing ordecreasing the retarding drag on the rotating unbalanced member 20 orboth. .The effective driving :force exerted on the unbalanced member 20may be varied by altering the number, shape or ,V size of the abutmentmember 25 within the recess 24 or by changing to a liquid having adifferent viscosity'rating. The retarding drag on the rotatingunbalanced member 20 may be varied by changing thedepth and number ofserrations 23 .onthe peripheral surface of the unbalanced member or bychanging to a liquid having a different Vviscosity rating or both. Ineach case the speed or rate 'of the unbalanced member 20 will be afunction of the size, shape and number of blades and abutments employed,the viscosity of the liquid, the serrations `and the rate of theimpeller.

Positioned on the cover I8 and in communication with the interior of thevessel Il is an expansion Abellows 21. The expansion bellows 21 providesa means .for relieving pressure within the vessel l'l such as may becaused by change in atmospheric pressure on the exterior of the deviceand thereby .prevents leakage of the liquid past the sealing member 2|.

The improved device of this invention is especially adapted to be usedin conjunction with airplanes although its use is by .no means limitedto such employment. When the device is in operation, as on an airplane,the parts tends to assume the position in which they are shown inFigures 1 and 4. The vessel l1 is horizontal and the spin axisofthevrotor is vertical as evidenced by the .positionof the shaft I6.With the device operating in this position, the clockwise rotation ofthe impeller builds up a pressure against the abutment member 25 whichrotates the unbalanced member 20 clockwise about its axis at a uniformrate. VThis rate of rotation differs from the rate of rotation of theimpeller and is maintained constant and uniform throughout eachrevolution as long as the spin axis of the rotor is vertical, by thedrag or resistance of the liquid in the vessel l1 on the peripheralsurface of the unbalanced member 20. The rate of rotation of theunbalanced member may be a few dozen revolutions per minute, while therate ofthe impeller maybe Vseveral thousand revolutions per minute.

Assume now that the spin axis of the rotor departs from its vertical orpredetermined position. Under such conditions, the position of thevessel I1 is .proportionately altered in respect to its normalhorizontal plane. This tilt of the vessel l1 now causes the rotationalmovement of the unbalanced member 2il to be uphill over one portion ofits travel and downhill vover another portion thereof. A further resultof the tilting -of the vessel l1 causes the movement of the unbalancedmember 20 over the uphill portion of its travel .to Vbe retarded and themovement over the downhill portion to be accelerated. Consequently, asubstantially stationary force isA exerted .on ,the spin axis of therotor during the slow .uphill travel of -the unbalanced member 2Dwhereas a force of equal magnitude is exerted on the spinaxis of therotor for a very short time during the fastdownhill travel of theunbalanced member 2U; the net difference. constitutes a precessing force,for the gyroscope .during the .uphill movement of the unbalanced member20. VNow, since gyroscopic pre- -cession is in a direction degrees fromthe direction ofthe .applied force ,and inthe direction of .rotation .ofthe rotor, the tilt is corrected by .pre-

cession of the spin axisto itsvertical position and the vessel l1 to itshorizontal position'by this net precessing force. Upon the return of thevessel to its horizontal position and the spin axis to its predeterminedposition, the unbalanced member 20 again takes up its uniform andconstant rate of rotation and the uphill and downhill travels areeliminated.

It will be apparent from the foregoing that herein is provided aresilient driving means operable to rotate a member at different ratesof speed within single revolutions While the driving element ismaintained at a constant rate of speed. Moreover, tre need for adjustingworn or impaired surfaces of frictional driving elements is totallyeliminated. It will also be apparent that means are provided forapplying a constant drag or resistance to the rotative movement withoutperiodic adjustments of retarding elements. Moreover, replacement ofparts damaged by heat and Wear caused by the engagement of conventionalfrictonal drag and driving elements is totally eliminated.

As it will be apparent to those skilled in the art to which the improveddevice appertains that numerous changes and widely different embodimentsof the invention may be made Without departing from the spirit and scopethereof, it is intended that the embodiment shown and the descriptionthereof shall be interpreted as illustrative and not in a limitingsense. Reference is therefore to be had to the appended claims for adefinition of the limits of the invention.

I claim as my invention:

l. In a gyroscope apparatus, the combination with a universally mountedrotatable member having a predetermined axis of spin, of means forreturning said axis to its predetermined position upon a departuretherefrom, said means comprising a rotatable body, fluid friction meansfor driving said body at a constant speed when said spin axis is in itspredetermined position, said fluid friction means for driving said bodycomprising a member positioned within said rotatable body and connectedto be driven at the same rate as said rotatable member, said body beingunbalanced to provide for retardation of its rotational movement due togravitational force when said spin axis departs from its predeterminedposition and thereby apply a net precessing force to said apparatuscausing it to precess toward said predetermined spin axis position.`

2. In a gyroscope apparatus, the combination with a universally mountedrotatable member positioned on a shaft and having a predetermined axisof spin, of means for returning said axis to its predetermined positionupon a departure therefrom, said means comprising an unbalancedrotatable body .positioned concentrically of said shaft and movableindependently thereof, a liquid receiving recess formed in said body, adriving member secured to said shaft and rotatable within said recess,liquid means within said recess for transmitting rotative force fromsaid driving member to said rotatable body, and means for retarding therotational movement of said body, said liquid and retarding means beingoperable to rotate said unbalanced body at an irregular rate duringsingle revolutions thereof when the rotatable member departs from itspredetermined spin axis whereby said member is caused to precess to itspredetermined position.

3. In a gyroscope apparatus, the combination with a universally mountedrotatable member positioned on a shaft and having a predetermined axisof spin, of means for returning said axis to its predeterminedpositionupon a departure therefrom, said means comprising an un- 6 balancedrotatable body positioned concentrically of said shaft and movableindependently thereof, a liquid receiving reces-s formed in said bod-y,a driving member secured to said shaft and rotatable Within said recess,liquid means within said recess for transmitting rotative force fromsaid driving member to said rotatable body, means fixed to said bodywithin said recess to assist in the transmission of said rotative force,said liquid and xed means being operable to cause movement of saidunbalanced body at irregular rates during single revolutions of saidunbalanced body when said rotatable member departs from itspredetermined axis of spin whereby said member is caused to precess toits predetermined position, and means for controlling the rate ofmovement of said rotatable body.

4. In a gyroscope having a predetermined axis of spin, means forreturning said axis to its predetermined position upon a departuretherefrom, said means comprising. an unbalanced member, and uid frictionmeans including an impeller activated by the operation of said gyroscopefor driving said unbalanced member at a constant rate when said axis isin its predetermined position and for operating said unbalanced memberat an irregular rate upon departure of said axis from its predeterminedposition to cause said gyroscope to precess to its predetermined axis ofspin.

5. In a gyroscope, means for maintaining the spin axis of said gyroscope.in a predetermined position, said means comprising an unbalanced memberhaving a recess formed therein and fluid friction means positioned insaid recess for driving said unbalanced member, said ii-uid frictionmeans including a body of viscous liquid in said recess, said fluidfriction means being operable to rotate said unbalanced member at aconstant rate When said axis is in its predetermined position and torotate said :member at an irregular rate upon departure of said axisfrom its predetermined position whereby precession causes said spin axisto return to its predetermined position.

6. In a gyroscope erecting means for maintaining the spin axis of saidgyroscope in a predetermined position and comprising, an unbalancedmember journaled for rotation about a pivot and having a recess formedtherein, driving means including an impeller extending into said recess,abutment means on said unbalanced member positioned Within said recess,and a liquid medi-um housed Within said recess and engaging saidimpeller and said abutment means, said impeller and said abutment meansbeing so arranged that liquid activated by said impeller is drivenagainst said abutment means to cause rotation of said journaled member.

7. A gyroscope erecting means for maintaining the spin axis of saidgyroscope in a predetermined position, comprising, a mass journaled forrotation about a pivot aligned with said spin axis, said mass beingdistributed to provide a greater Weight on one side of said pivot thanon the opposed side thereof, said mass having a recess formed therein,driving means extending into said recess, abutment means positionedwithin said recess and attached to said mass and a liquid medium housedWithin said recess and engaging said driving -means and said abutmentmeans, said driving means and said abutment means being so disposed`that liquid activated by said drive means is driven against saidabutment means to cause'rotation of said journaled mass.

8. A gyroscope erectingmeans,,comprisingan unbalanced mass rotatableabout apivot, iiuid friction drive means including an impeller forcausing rotation of said mass at a uniform rate When the spin axis ofsaid gyroscope is ina predetermined position and for causing rotationofsaid mass at an irregular rate when the spin axis of said gyroscopedeparts .from said predetermined position, and means yieldably resistingthe rotational movement of said mass.

9. A gyroscope apparatus comprising the combination with a universallymounted mass positioned on a shaft and having a predetermined axis ofspin of means for returning said axis to its predetermined position upona departure therefrom, said means including a fiat circular vesselhaving a flanged peripheral surface and being centrally apertured toreceive said shaft, a circular member having a kerfed peripheral surfacenested Withinsaid vessel and being provided with a central aperturethrough which said shaft extends, said circular member beingrotationally movable relative to said shaft and said vessel, a liquidreceiving circular recess formed in said circular member `eccentricallythereof, an impeller member fixed toa portion of said shaft within saidrecess and rotatable with said shaft, abutment means positioned withinsaid recess and fixed to said circular member, a body of liquid in saidvessel and said recess, and closure means for hermetically sealing theinterior of said vessel.

10. In a, gyroscope erecting apparatus comprising in combination, ashaft, a cylindrical vessel having an open end and a closed end, theclosed end of said vessel having a centrally disposed aperture throughwhich said shaft extends, a circular member having a central aperturethrough which said shaft extends positioned within said vessel, saidcircular member having a circular recess formed eccentrically therein,an impeller member fixed to said shaft and rotatable within said recessupon rotation of said shaft, abutment means positioned within saidrecess and fixed to said circular member, a body of liquid positionedwithin said recess and said vessel, said impeller, said abutment meansand said body of liquid being disposed to provide a drivingconnectionbetween said shaft and said circular member, and closure means forsealing the open end of said cylindrical member.

1l. In a gyroscope erecting apparatus, a vessel having an aperturetherein, a centrally apertured member positioned within said vessel withsaid apertures in alignment, said centrally apertured member having aliquid receiving recess formed therein eccentrically of the aperture insaid member, abutment means fixed to said apertured member within saidrecess, a shaft extending through said aligned apertures and terminatingWithin said recess, an impeller carried by said shaft, a quantity ofliquid positioned Within said vessel and the recess of said centrallytapertured member, said impeller said liquid'in said recess and saidabutment means being arranged to provide a driving connection betweensaid shaft and said centrally apertured member whereby said member maybe rotated about an axis formed by said shaft, the liquid in said vesselfunctioning to retard by engagement with the peripheral surface of saidcentrally apertured member, and closure means for sealing said vessel.

12. In a gyroscope erecting device, in'combination: a vessel; a firstmember mounted'for rotation in said vessel and includinga recess; asecond member mounted for rotation in said recess about the axis ofrotation of said rst member; means including a viscous fluid in saidrecess for causing rotation of said rst member on rotation of saidsecond member; and means including a viscous fluid in said vessel foropposing rotation of said first member, so that said rst member maynormally rotate at a constant speed.

13. Ina gyroscope erecting device, in combination: a vessel; a rstmember mounted for rotation in said vessel and including a recess; a,second member mounted for rotation in said recess 'about the axis ofrotation of said first member; means including a viscous fluid in said`recess for causing rotation vof said first member i on rotation of saidsecond member; and means including a viscous fluid in said vessel foropposing rotation of said rst member so that said first member maynormally rotate at :a constant speed; said recess being eccentric ofsaid axis, so that' if said axis is not vertical' the angular velocityof said first member varies at various rotated positions of said firstmember.

14. In a gyro erecting device, in combination: a vessel; a rst membermounted for rotation in said vessel and including a recess; a secondmember mounted for rotation in said recess about the axis of rotation ofsaid-first member; means including a viscous fluid in said recess forcausing rotation of said rst member onrotation of said second mein-ber;means including a viscous fluid in said vessel for opposing rotation ofsaid rst member `so that said first member may normally rotate at aconstant speed, said recess being eccentric of said axis, so that ifsaid axis is not vertical the angular velocity of said first membervaries at various rotated posi-tions of said first member; and meansmounting said vessel for rotary movement about axes normal to said rstnamed axis, so that when said first axis is vertical the average torqueproduced by said first member about each .of said axes is Zero, whilewhen said axis isnot vertical said average torque has a value other`than zero, due to the variations `in said angular velocity of saidfirst member.

15. in a device ofthe class described, in combination, a lnormallyenergized gyroscope having a normally vertical spin axis, gravityresponsive means for changing the attitude of said axis with respect tothe vertical, and fluid friction means drivingly coupling said gravityresponsive means and said gyroscope to provide an erecting force to saidgyroscope When its spin axis .departs from said normal verticalattitude.

FRED P. STROTHER.

REFERENCES .CITED i The following references are of record in the leofthis patent:

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